Answer:
One when it enters the glass slab from air and second time when it enters the air through glass slab. When light rays travelling through air enters glass slab, they get refracted and bend towards the normal. Now the direction of refracted ray changes again when it comes out of the glass slab into air.
Answer:
The value of spring constant is 266.01 
Explanation:
Given:
Mass of pellet
kg
Height difference of pellet rise
m
Spring compression
m
From energy conservation law,
Spring potential energy is stored into potential energy,

Where
spring constant, 



Therefore, the value of spring constant is 266.01 
Kinetic energy. thermal energy (a low form of energy ) is a form of kinetic energy as it is produced as a result of motion of particles either if they vibrate at their position or they move along longer paths. Motion produces friction or resistance which leads to excitation and thus the heat is produced. The higher the motion of the particles, the higher would be the thermal energy.
The angle of reflection is equal to angle of incidence so the angle of reflection is also 32°.
Alaska- Subartic Climate
Portland, Oregon- Marine West Coast Climate
Key West, Florida- Tropical Savannah Climate